Cutting knife-stack support



July y16, 1963 v c. THUMIM 3,097,752

QUTTING KNIFE-STACK SUPPORT AFiled Oct. 12,.l960 2 Sheets-Sheet 1 July16, 1963 c. THUMIM 3,097,752

- CUTTING KNIFE-STACK SUPPORT Filed Oct. l2, 1960 2 Smets-sheet 2 INV ENTOR. CTF/H y/W//W United States Patent Omce 3,097,752 Patented July 16,1963 3,097,752 l CUTIING KNIFE-STACK SUPPORTV `Carl Thum'im, Westbury,N.Y., assignor to Miehle-Goss- Dexter, Incorporated, Chicago, Ill., acorporation of Delaware Filed Oct. 12, 1960, Ser. No. 62,178 `9 Claims.(Cl. 214-'-1) My .present invention is an improvement, including a novelvalve construction, of the invention shown in my prior Patent 2,771-,948for a Cutting Knife-Stack Support and relates to a novel air cushionvalve which will facilitate the movement of the paper stack on the tableof the cutting machine as the stack is manipulated for placement and forcutting.

The primary object of my invention is the provision of a novel valvestructure yfor the openings of an air cushion cutting table wherein thepaper stack under surface and the boundaries thereof control the number:and distribution of the openings through which air under Vpressure isadmitted to form a cushion of air under `the paper stack to facilitatethe movement of the stack.

Speciiically my novel valve comprises a structure where a 4ball or othervalve element is held in position by compressed air to close the openingin the table Iand prevent Vair under pressure from escaping; the balldoes not project 'above the table surface. A srnall by-pass -groove inthe opening permits a correspondingly small amount of air lto escape tothe enclosed (tubular) passage to the `opening above the valve seat.VWhen any portion of the paper stack covers the opening, this smallamount of `escaping air quickly, land almost immediately, builds up lanequal counter-pressure in the passage above the valve seat therebypermitting the ball valve to drop and permit compressed air to escapethrough the opening at the end of the small passage. 'This provides theair cushionfor the paper stack.

sectioned, of one of the valves used to control air to the plurality ofports.

`FIGURE 4 is a sectional view taken lalong line 5--5 of FIGURE 2 lookingin the direction of the arrows.

FIGURE 5 is an electrical diagram showing the mode of connecting certaincomponents of the invention.

Referring now to the drawings, there is shown as much of theconstruction of the cutting machine Ias isV necessary lto render thedescription of the present invention clear vand lucid. Brieily, theillustrative cutting machine inncludes a main frame F carrying ahorizontally extendving cutting table T, a vertically displaceablecutting knife .K, la paper clamp C `arranged rearwardly of the cuttingknife K and lowered against the paper lift with pressure `prior tocutting and a back gauge G selectively positioned on the cutting table Tto move the paper lift into position -for cutting. The back gauge G isdriven toward and `away from the knife K by A:a lead screw in' threadedengagement with an integral head on the back gauge G,

the lead screw 10 being coupled to a hand wheel 12 adjacent the `forwardend of the machine and to a drive motor 14 `adjacent the rearward end ofthe machine.

The table T is provided with a plurality of rows of spaced ports or airexits 20, distributed uniformly about the paper supporting surface 22 ofthe table T. The number of ports Ztl is Kselected in' accordance withthe 2 floating action required as will 'subsequently become apparent.The respective ports are interconnected by internal tubes or passageways24 'in the table T to a common tube or inlet 26 adapted to be connectedto a suitable source of air under pressure.

Specifically, an 'air pump 28 constructed Iand arranged in accordancewith principles well understood per se is connected via appropriategearing 30 to sa drive motor 32. The high pressure outlet 34 of the pump28 is connected to a high pressure reservoir 36 and then to a lowVpressure reservoir` 38 via a reducing valve 40. 'Ilhe low pressurereservoir is connected to the 'air inlet 26 by an electrically operatedthree-way valve v42 normally closed and illustrated as a solenoidcontrolled valve having a solenoid plunger 44 arranged in controlledrelation relative to the solenoid coil 46.

A suitable source of line potential 48, 48 is provided for the solenoidcoil 46 which forms part of ak control circuit arranged to coordinatethe admission of air to the ports v20 in' dependence upon operation ofthe back gauge G, the clamp C, and cutting knife K. Specifically,

Ywhen the clamp C is brought into contact with the paper prior ftooperation of the cutting knife K, it is undesirable to admit air to theinlet 24 via the normally closed yair inletvalve 42, since this mightresult in sidewise displacement of the paper upon engagement therewithof the clamp C. Accordingly, in circuit with a manual operators switch50, the closing of which would 'normallyr complete the energizingcircuit for the solenoid coil 46, there is provided 'a circuit breaker52 including xed contacts 54, 54 and a movable bridging contact 56supported on one end of a rocking lever 58 pivoted on a pin 60. A spring62 is connected to the lever 58 and normally biases the same to theposition indicated by the broken lines of FIGURE 1 wherein the circuitbreaker 52 is open.

The end of the lever 58 remote from the connection to biasing spring 62is arranged to overlie the pin 64. Therefore, as the clamp assemblymoves from the inop- .erative or retracted position illustrated by thefull lines of FIGURE 1 tothe clamping or extended position illusltratedby the broken lines, the lever 58 rocks in the counter-clockwisedirection due to the -bias of spring 62 to open the circuit breaker 52.Since the clamp C moves downwardly just prior to .a cutting operation,it follows that Iair supply to the ports 20 will be precluded duringcutting as well las clamping. Of course, return of the clamp C to theretracted or inoperative position results in a closing of the circuitbreaker 52 and return to control by the manual switch 50.

A further instance when it is necessary lto preclude Iair supply to Itheports 20 is when the back ygauge G is in motion to position the paperrelative to the knife K. At such times, floating of the paper mightcause an overtravel of the paper relative to the adjusted position towhich the paper is brought by the back :gauge G. To obviate thisdiiculty, a further switch 66 is connected .in the solenoid controlcircuit, this switch being connected in controlled relation to the backgauge motor 14, i.e., in electrical parallel therewith as shown inFIGURE 6, precluding the possibility of activating the solenoid coil 46when the back Igauge G is being adjusted. As a .fur-ther, feature, thethree-way valve 42 is arranged to open' 'the air inlet 26 to theatmosphere whenever the supply from the low pressure reservoir 38 is cutoff, Athereby releasing any lifting pressure which might be availableIat the ports 20 of the table T as a result of prior introduction oflair under pressure to the table T.

The operating mechanism for the back gauge G, the clamp C, the cuttingknife K and thetm'echanism for supplying the compressed air to the portsmay be understood from the above mentioned patent and are not ret oquired for a full understanding of the present novel valve. Referringnow to FIGURES 3, 4, and 5, each of my novel valves 70 is mounted in acircular opening T to form the plurality of ports 2t).

Each valve 70 comprises, in part, a bushing 71 which fits within thecircular cutout in a press fit. A shelf 77 is formed internally ofbushing 71 and forms the bottom Aof ball chamber 79. The lower chamberof bushing 71 receives air conduit 80. A hole 81 in shelf 77 provides apath for the compressed air from conduit 80 to the chamber 79. The topof bushing 71 is internally threaded to receive externally threadedbushing 72, which forms the top of ball chamber 79. Bushing 71 isfurther provided with lip 73 and groove 75. When valve 70 is assembledO-ring 74 is placed within groove v75 and bushing 72 is turned intobushing 71 until the bottom abuts lip 73. Thus, an air tight connectionis formed between the bushings. `Bushing 72 is provided with anoctagonal aperture 76 at its upper end.

In operation after air pressure is established, the aperture is sealedby ball 78, which is maintained in position by air pressure, as shown inFIGURE 3.

A small groove 81a, at the top of bushing 72, communicates with bothball chamber 79 and aperture 76 to provide automatic control of theposition of valve ball 78 in accordance with the position of the paperstack as described below.

The ball will seat against the conical surface in which the groove 81ais cut, since it is tangent thereto and such surface is below theoctagonal aperture. It should be noted that the aperture itself is notthe valve seat.

When there is no stack covering the port 20, the pressure of thecompressed air in ball chamber 79 forces ball 78 upwards to sealaperture 76. The small amount of air leaking through groove 81a isexhausted to the area above the ball 78. The groove 81a is sufficientlysmall in cross-section so that when the area above it is not closed,pressure in ball chamber 79 maintains ball 78 in closed (upward)position.

When a stack of paper covers port 20, the volume between hexagonalaperture 76 and the top of ball 78 forms a chamber of its own, as shownin FIGURE 3, with the stack closing the top of the chamber. Air escapingthrough groove 81 now quickly lls the small chamber until the pressureabove the ball 78 will equal the pressure below the ball. The ball will,therefore, drop, due to gravity, thereby permitting free flow of thecompressed air, through octagonal aperture 76, to facilitatemaneuverability of the stack.

By this means, therefore, the small groove 81a provides automaticcontrol of the position of ball valve 78. When the paper stack traps theair leaking from groove 81a, the equalization of pressures opens thevalve to full flow of compressed air. When the stack leaves the openingabove any particular valve, the drop in pressure above the ball 78permits the air under pressure to close the valve. The smallness of thechamber above the ball valve 78 ensures that the opening of the valveWill occur very rapidly. Closing of the valve will also be almostinstantaneous owing to the dumping of air above the ball 78 when thestack leaves the port.

In the foregoing I have described my invention solely in connection withspecific illustrative embodiments thereof. Since many variations andmodifications of my invention will now become apparent to those skilledin the art, I prefer not to be bound by the specic disclosures hereincontained but only by the appended claims.

I claim:

il. In a paper cutting machine, a horizontal table for supporting apaper stack; a plurality of openings in said table; a valve structurefor each opening; each valve structure comprising a chamber having avalve seat at its upper end, a passage between the valve seat and theopening and a valve in said chamber; a compressed air entry port intosaid chamber; a by-pass passage connecting the portion of said chamberbelow the valve seat with the iirst mentioned passage between said valveseat and said opening, wherein said stack normally covers said openingsand compressed air maintains said valves against said seats untilpressure is equalized on said valves due to air by-passing into saidfirst-mentioned passages, eiective to permit opening of said valves torender air support for said stack, and wherein said valves close due toair pressure thereon when said stack is removed.

2. In a paper cutting machine, a horizontal table for supporting a paperstack; a plurality of openings in said table; a valve structure for eachopening; each valve structure comprising a chamber having a valve seatat its upper end, a passage between the valve seat and the opening and avalve in said chamber; a compressed air entry port into said chamber; aby-pass passage connecting the portion of said chamber below the valveseat with the lirst mentioned passage between said valve seat and saidopening; said by-pass passage having a cross-section which is relativelysmall compared to the cross-sections of the chamber, the diameter of thevalve seat and the cross-section of the lirst mentioned passage, whereinsaid stack normally covers said openings and compressed air maintainssaid valves against said seats until pressure is equalized on saidvalves due to air by-passing into said first-mentioned passages,effective to permit opening of said valves to render air support forsaid stack, and wherein said valves close due to air pressure thereonwhen said stack is removed.

3. In a paper cutting machine, a horizontal table for supporting a paperstack; a plurality of openings in said table; a valve structure for eachopening; each valve structure comprising a chamber having a valve seatat its upper end, a passage between the valve seat and the opening and avalve in said chamber; a compressed air entry port into said chamber; aby-pass passage connecting the portion of said chamber below the valveseat with the iirst mentioned passage between said valve seat and saidopening; said by-pass passage having a cross-section which is relativelysmall compared to the cross-sections of the chamber, the diameter of thevalve seat and the crosssection of the iirst mentioned passage;compressed air, when introduced in said chamber', driving said valveagainst said valve seat, wherein said stack normally covers saidopenings and compressed air maintains said valves against said seatsuntil pressure is equalized on said valves due to air by-passing intosaid nist-mentioned passages, effective to permit opening of said valvesto render air support for said stack, and wherein said valves close dueto air pressure thereon when said stack is removed.

4. In a paper cutting machine, a horizontal table for supporting a paperstack; a plurality of openings in said table; a valve structure for eachopening; each valve structure comprising a chamber having a valve seatat its upper end, a passage between the 'valve seat and the opening anda valve in said chamber; a compressed air entry port into said chamber;a by-pass passage connecting the portion of said chamber below the valveseat with the first mentioned passage between said valve seat and saidopening; said by-pass passage having a crosssection which is relativelysmall compared to the crosssections of the chamber, the diameter of thevalve seat and the cross-section of the iirst mentioned passage;cornpressed air, when introduced in said chamber, driving said valveagainst said valve seat; said by-pass passage permitting a leakage ofair under pressure to said rst mentioned passage and through saidopening, wherein said stack normally covers said openings and compressedair maintains said valves against said seats until pressure is equalizedon said valves due to air by-passing into said rst-mentioned passages,effective to permit opening of said valves to render air support forsaid stack, and wherein said valves close due to air pressure thereonwhen said stack is removed. y

5. vIn a paper cutting machine, a horizontal table for supporting apaper stack; a plurality of openings in said table; ya valve structurefor each opening; each valve structure comprising a chamber having avalve seat at its upper end, a passage between the valve seat and theopening and a valve in said chamber; la compressed air entry port intosaid chamber; a by-pass passage connecting the portion of said chamberbelow the valve seat with the rst mentioned passage between said valveseat and said opening; sa-id Ab-y-pass passage having a cross-sectionwhich is relatively small compared to the cross-sections of the chamber,the diameter of the valve seat and the cross-section of the Afirstmentioned passage; compressed air, when introduced in said chamber,driving said valve against said valve seat; said by-pass passagepermitting a leakage of air under pressure to said iirst mentionedpassage and through said opening; said ttirst mentioned passage, whenthe opening is covered by a paper stack, being iillled with air underpressure from said by-pass passage equalizing the pressure below thevalve and permitting the valve to open.

6. In a paper cutting machine, a horizontal table for supporting a paperstack; a plurality `of openings in said table; a valve structure foreach opening; each valve structure comprising a chamber having a valveseat at its upper end, a passage between the valve seat and the openingand a valve in said chamber; a compressed air entry port into saidchamber; a by-pass passage connecting the portion of said chamberbelowthe valve seat with the irst mentioned passage lbetween said valve seatand said opening; said by-pass passage 'having la cross-section which isrelatively small compared to the cross-sections of the chamber, thediameter of the valve seat :and the cross-section of the tirst mentionedpassage; compressed air, when introduced in said chamber, driving saidvalve against said valve seat; said by-pass passage permitting a leakageof air under pressure to said first mentioned passage Iand through saidopening; said rst mentioned passage, when the opening is cove-red by lapaper stack, being iilled with air under pressure -from said `by-passpassage equalizing the pressure below the valve and permitting the valveto open; the compressed air in said tirst mentioned passage being dumpedwhen the paper stack leaves the opening to establish la pressuredierential which closes said valve.

7. In a paper cutting machine, a horizontal table for supporting a paperstack; a plurallity of openings in said table; la valve structure foreach opening; each valve structure comprising a chamber having acircular valve seat at its upper end, a passage between the valve seatand the opening and Ia ball valve in said chamber; a compressed airentry port into said chamber; a by-pass passage connecting the portionof said chamber below the valve seat with the rst mentioned passagebetween said valve seat and said opening, wherein said stack normallycovers said openings and compressed air maintains said valves againstsaid seats until pressure is equalized on said valves due to airby-passing into said rst-mentioned passages, effective to permit openingof said valves to render air support for said stack, and wherein saidvalves close due to air pressure thereon when said stack is removed.

8. In a paper cutting machine, a horizontal table for supporting a paperstack; a plurality of openings in said table; a valve structure for eachopening; each valve structure comprising a chamber having a circularvalve seat at its upper end, a passage between the valve seat and theopening and a ball valve in said chamber; a compressed air entry portinto said chamber; a {by-pass passage connecting the portion of saidchamber below the valve seat 'with the iirst mentioned passage betweensaid valve seat and said opening; said by-pass passage having across-section which is relatively small compared to the cross-sectionsof the chamber, the Idiameter of the valve seat and the cross-section ofthe rst mentioned passage; compressed air, when introduced in sai-dchamber, driving said valve against said valve seat; said by-passpassage permitting a leakage of air under pressure to said rst mentionedpass-age and through said opening; said irst 'mentioned passage, whenthe opening is covered by a paper stack, being lilled with air underpressure from said by-pass passage equalizing the pressure below thevalve and permitting the valve to open; the compressed fair in saidfirst mentioned passage being dumped when the paper stack `leaves theopening to establish a pressure differential which closes said valve.

9. in a paper cutting machine, a horizontal table for supporting a paperstack; a plurality of openings in said table; a valve structure for eachopening; each valve structure comprising a chamber having a valve seatat its upper end, a passage between the valve seat and the opening and aball valve in said chamber; a compressed air entry port into saidchamber; a by-pass passage connecting the portion of said chamber belowthe valve seat with the first-mentioned passage between said valve seatIand said opening, a closure member threadedly secured to each valvestructure and having a top 'wall formed with said opening, said openingbeing shaped to accommodate a tool, whereby said closure members may bethreadedlly adjusted into flush relationship between said top Walls landsaid table.

References Cited in the file of this patent UNITED STATES PATENTS1,668,271 Fisk May 1, 1928 2,065,161 Thompson Dec. 22, 1936 2,176,307Lamb Oct. 17, 1939 2,310,636 Howard Feb. 9, 1943 2,576,687 Krenbiel Nov.27, 1951 2,733,960 Barford Feb. 7, 1956 2,945,600 Thumim July 19, 1960

1. IN A PAPER CUTTING MACHINE, A HORIZONTAL TABLE FOR SUPPORTING A PAPERSTACK; A PLURALITY OF OPENINGS IN SAID TABLE; A VALVE STRUCTURE FOR EACHOPENING; EACH VALVE STRUCTURE COMPRISING A CHAMBER HAVING A VALVE SEATAT ITS UPPER END, A PASSAGE BETWEEN THE VALVE SEAT AND THE OPENING AND AVALVE IN SAID CHAMBER; A COMPRESSED AIR ENTRY PORT INTO SAID CHAMBER; ABY-PASS PASSAGE CONNECTING THE PORTION OF SAID CHAMBER BELOW THE VALVESEAT WITH THE FIRST MENTIONED PASSAGE BETWEEN SAID VALVE SEAT AND SAIDOPENING, WHEREIN SAID STACK NORMALLY COVERS SAID OPENINGS AND COMPRESSEDAIR MAINTAINS SAID VALVES AGAINST SAID SEATS UNTIL PRESSURE IS EQUALIZEDON SAID VALVES DUE TO AIR BY-PASSING INTO SAID FIRST-MENTIONED PASSAGES,EFFECTIVE TO PERMIT OPENING OF SAID VALVES TO RENDER AIR SUPPORT FORSAID STACK, AND WHEREIN SAID VALVES CLOSE DUE PRESSURE THEREON WHEN SAIDSTACK IS REMOVED.